JEE & NEETJEE Mathematics JEE Main Maths 100+ MCQ & Answer | Page-05 | JEE & NEET MCQ February 4, 2025 DSN MARATHI 41. Let * be a binary operation on Q, defined by a * b = 3ab5 is A. Commutative B. Associative C. Both (a) and (b) D. None of these Answer Option : C 42. Let * be a binary operation on set Q of rational numbers defined as a * b = ab5. Write the identity for A. 5 B. 3 C. 1 D. 6 Answer Option : A 43. Find the identity element in the set I+ of all positive integers defined by a * b = a + b for all a, b ∈ I+ A. 1 B. 2 C. 3 D. 0 Answer Option : D 44. Let * be a binary operation on set Q – {1} defind by a * b = a + b – ab : a, b ∈ Q – {1}. Then * is A. Commutative B. Associative C. Both (a) and (b) D. None of these Answer Option : C 45. The binary operation * defined on N by a * b = a + b + ab for all a, b ∈ N is A. commutative only B. associative only C. both commutative and associative D. none of these Answer Option : C 46. The number of commutative binary operation that can be defined on a set of 2 elements is A. 8 B. 6 C. 4 D. 2 Answer Option : D 47. Let T be the set of all triangles in the Euclidean plane, and let a relation R on T be defined as aRb if a is congruent to b ∀ a, b ∈ T. Then R is A. reflexive but not transitive B. transitive but not symmetric C. equivalence D. None of these Answer Option : C 48. The maximum number of equivalence relations on the set A = {1, 2, 3} are A. 1 B. 2 C. 3 D. 5 Answer Option : D 49. Let us define a relation R in R as aRb if a ≥ b. Then R is A. an equivalence relation B. reflexive, transitive but not symmetric C. symmetric, transitive but not reflexive D. neither transitive nor reflexive but symmetric Answer Option : B 50. Let R be the relation “is congruent to” on the set of all triangles in a plane is A. reflexive B. symmetric C. symmetric and reflexive D. equivalence Answer Option : D
41. Let * be a binary operation on Q, defined by a * b = 3ab5 is A. Commutative B. Associative C. Both (a) and (b) D. None of these Answer Option : C
42. Let * be a binary operation on set Q of rational numbers defined as a * b = ab5. Write the identity for A. 5 B. 3 C. 1 D. 6 Answer Option : A
43. Find the identity element in the set I+ of all positive integers defined by a * b = a + b for all a, b ∈ I+ A. 1 B. 2 C. 3 D. 0 Answer Option : D
44. Let * be a binary operation on set Q – {1} defind by a * b = a + b – ab : a, b ∈ Q – {1}. Then * is A. Commutative B. Associative C. Both (a) and (b) D. None of these Answer Option : C
45. The binary operation * defined on N by a * b = a + b + ab for all a, b ∈ N is A. commutative only B. associative only C. both commutative and associative D. none of these Answer Option : C
46. The number of commutative binary operation that can be defined on a set of 2 elements is A. 8 B. 6 C. 4 D. 2 Answer Option : D
47. Let T be the set of all triangles in the Euclidean plane, and let a relation R on T be defined as aRb if a is congruent to b ∀ a, b ∈ T. Then R is A. reflexive but not transitive B. transitive but not symmetric C. equivalence D. None of these Answer Option : C
48. The maximum number of equivalence relations on the set A = {1, 2, 3} are A. 1 B. 2 C. 3 D. 5 Answer Option : D
49. Let us define a relation R in R as aRb if a ≥ b. Then R is A. an equivalence relation B. reflexive, transitive but not symmetric C. symmetric, transitive but not reflexive D. neither transitive nor reflexive but symmetric Answer Option : B
50. Let R be the relation “is congruent to” on the set of all triangles in a plane is A. reflexive B. symmetric C. symmetric and reflexive D. equivalence Answer Option : D
